NONQUALIFIED STOCK OPTION AGREEMENT                NQSO-012


     THIS NONQUALIFIED STOCK OPTION AGREEMENT ("Agreement") is made and 
entered into on July 3, 1995, by and between TINSLEY LABORATORIES, INC., a 
California corporation ("Company"), and DANIEL J. DUCKHORN ("Optionee").

     1.   GRANT OF OPTION.  The Company hereby irrevocably grants to the 
Optionee, on the terms and subject to the conditions set forth in this 
Agreement, the right and option ("Option") to purchase all or any part of an 
aggregate of 5,000 shares ("Option Shares") of the Company's common stock, 
such number being subject to adjustment as provided in Section 8 hereof.  It 
is understood by the parties hereto that the Option is not intended to 
qualify as an "incentive stock option" within the meaning of Section 422 of 
the Internal Revenue Code of 1986, as amended (the "Code").  If Optionee is 
an employee of the Company or a parent or a subsidiary of the Company, it is 
further understood by the parties hereto that the Option has been granted as 
a matter of separate inducement and agreement in connection with the 
employment of the Optionee and is not in lieu of any salary or other 
compensation for the Optionee's services.

     2.   OPTION EXERCISE PRICE.  The exercise price for the Option Shares 
shall be $7.00 per share.  The exercise price shall be paid in full as 
provided in Section 9 hereof.

     3.   TERM OF OPTION.  The term of the Option shall be for a period of 
five (5) years from the date hereof, subject to earlier termination as 
provided in Section 7 hereof.

     4.   EXERCISABILITY OF OPTION.

          (a)  Subject to the provisions of Section 4(b) hereof, the Option 
shall be exercisable as to all of the Option Shares throughout the term 
hereof.

          (b)  The Company's grant of the Option is based upon the assumption 
that the Optionee's exercise of the Option and the Company's issuance of the 
Option Shares as a result of such exercise will be exempt from registration 
under the Securities Act of 1933, as amended (the "Securities Act").  In the 
event that the Company's assumption is erroneous, the Option may not be 
exercised unless and until a registration statement under the Securities Act 
relating to the Option Shares shall be in effect, or unless and until the 
issuance of the Option Shares upon the exercise of the Option shall be exempt 
from registration under the Securities Act, in either of which events the 
term of the Option shall be deemed to have been automatically extended 
through and including a period of ninety (90) days from and after the date 
that such registration statement under the Securities Act relating to the 
Option Shares first becomes effective or the date that the issuance of the 

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Option Shares upon the exercise of the Option first becomes exempt from 
registration under the Securities Act, as the case may be.  In this regard, 
the Company shall use its best efforts to either register the Option Shares 
in accordance with the registration requirements of the Securities Act or to 
comply with any exemption therefrom with regard to the issuance of the Option 
Shares.  The Company shall promptly notify Optionee of any automatic 
extension in the term of the Option in the event the foregoing provisions 
become applicable.  In all events, the Optionee shall give a written 
representation satisfactory to legal counsel to the Company upon his exercise 
of the Option that he is acquiring the Option Shares for investment purposes 
and not with a view to, or for resale in connection with, the distribution of 
any Option Shares or other securities of the Company.

     5.   LIMITATION ON OPTIONEE'S RIGHTS.

          (a)  The Optionee shall not have any of the rights of a shareholder 
of the Company with respect to the Option Shares except to the extent that 
one or more certificates for the Option Shares shall be delivered to him upon 
the due exercise of the Option.

          (b)  If Optionee is an employee of the Company or a parent or a 
subsidiary of the Company, nothing contained in this Agreement shall confer 
upon the Optionee any right with respect to the continuation of his 
employment by the Company or a parent or a subsidiary of the Company or 
interfere in any way with the right of the Company or a parent or a 
subsidiary of the Company (subject to the terms of any separate employment 
agreement to the contrary) to terminate his employment at any time or to 
increase or decrease the compensation payable to the Optionee.

     6.   NONTRANSFERABILITY OF OPTION.  The Option shall not be transferable 
by the Optionee otherwise than by will or the laws of descent and 
distribution, and the Option may be exercised during the lifetime of the 
Optionee only by him. More particularly, but without limiting the generality 
of the foregoing, the Option may not be assigned, transferred (except upon 
the death of the Optionee), pledged or hypothecated in any way, shall not be 
assignable by operation of law and shall not be subject to execution, 
attachment or similar process.  Any attempted assignment, transfer, pledge, 
hypothecation or other disposition of the Option contrary to the provisions 
hereof, and the levy of any execution, attachment or similar process upon the 
Option, shall be null and void and without effect.

     7.   TERMINATION OF OPTION UPON COMPANY'S ACQUISITION.  In the event 
that the Company is involved in a merger, consolidation or other combination 
with one or more other corporations in which the Company is not the surviving 
corporation or in the event that the Company is liquidated and dissolved 
following the Company's sale of all, or substantially all, of its operating 
assets and goodwill to another corporation, the Option shall terminate as of 
the effective date of such merger, consolidation or other combination 


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or as of the effective date of such sale of this corporation's operating 
assets and goodwill, as the case may be, to the extent that the Option has 
not theretofore been exercised by the Optionee and/or is not agreed to be 
assumed by, or replaced by equivalent options granted by, the surviving 
corporation in such merger, consolidation or other combination or the 
purchasing corporation in such sale of this corporation's operating assets 
and goodwill.

     8.   CHANGES IN CAPITAL STRUCTURE.  In the event that the outstanding 
shares of common stock of the Company are changed into or exchanged for a 
different number or kind of shares or other securities of the Company or of 
another corporation by reason of merger, consolidation, combination, 
reorganization, recapitalization, reclassification, combination of shares, 
stock dividend, stock split or reverse stock split, the rights of the 
Optionee shall be appropriately adjusted both as to the number of shares and 
the Option exercise price.

     9.   METHOD OF EXERCISING OPTION.

          (a)  Subject to the terms and conditions of this Agreement, the 
Option may be exercised by written notice ("Exercise Notice") from the 
Optionee or other person entitled to exercise the Option delivered to the 
Company stating the election to exercise the Option and the number of the 
Option Shares in respect of which it is being exercised, and shall be signed 
and dated by the person or persons so exercising the Option.  The Exercise 
Notice shall be accompanied by the full exercise price for the Option Shares 
in respect of which the Option is being exercised.  In the event the Option 
shall be exercised by any person or persons other than the Optionee, the 
Exercise Notice shall be accompanied by appropriate proof of the right of 
such person or persons to exercise the Option.

          (b)  Payment of the exercise price shall be made by the delivery of 
a bank cashier's check, personal check or the equivalent thereof payable to 
the order of the Company, by the delivery of shares of the Company's common 
stock duly endorsed in favor of the Company or accompanied by a duly executed 
stock power in favor of the Company or by a combination of the foregoing.  If 
shares of the Company's common stock are delivered in full or partial payment 
of the aggregate exercise price, such shares shall be valued at the average 
of the per share closing bid and asked prices for shares of the Company's 
common stock in the over-the-counter market on the date immediately preceding 
the date the Exercise Notice is dated or, in the absence of any reported 
sales on such date, the first preceding date on which there were such sales.

          (c)  The certificate or certificates for the Option Shares in 
respect of which the Option shall have been exercised shall be registered in 
the name of the person or persons exercising the Option, or, if the Option is 
exercised by the Optionee and if the Optionee shall so request in the 
Exercise Notice, shall be registered in the name of the 


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Optionee and another person jointly, with right of survivorship, and shall be 
delivered as provided above to or upon the written order of the person or 
persons exercising the Option.

All of the Option Shares purchased upon the exercise of the Option as 
provided herein shall, when issued, be fully paid and nonassessable.

     10.  ADEQUATE AUTHORIZED CAPITALIZATION.  The Company shall at all times 
during the term of the Option reserve and keep available or otherwise have 
authorized such number of shares of the Company's common stock as will be 
sufficient to satisfy the requirements of this Agreement, shall pay all fees 
and expenses necessarily incurred by the Company in connection therewith, and 
shall from time to time use its best efforts to comply with all laws and 
regulations which, in the opinion of legal counsel to the Company, shall be 
applicable thereto.

     11.  NOTICES.  All notices, requests, demands and other communications 
called for or contemplated hereunder shall be in writing and shall be deemed 
to have been duly given when personally delivered or when mailed by United 
States certified or registered mail, postage prepaid, addressed to the 
following parties or their successors in interest at the following addresses, 
or at such other addresses as the parties may designate by written notice in 
the manner aforesaid:

     If to the Company:              Tinsley Laboratories, Inc.
                                     3900 Lakeside Drive 
                                     Richmond, CA  94802 
                                     Attn:  President

     If to Optionee:                 3027 Silverado Trail
                                     St. Helena, CA  94574

     12.  SUCCESSORS AND ASSIGNS.  Subject to the limitations on 
transferability contained in Section 6 hereof, this Agreement shall be 
binding upon and shall inure to the benefit of the parties hereto, the 
Company's successors in interest and assigns, and the Optionee's permitted 
successors in interest. 


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      13.  APPLICABLE LAW.  This Agreement shall be construed and enforced in 
accordance with the laws of the State of California.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement on 
the date first above written.

        "Company"                                       "Optionee"

TINSLEY LABORATORIES, INC. 


By: /s/ Robert J. Aronno                        /s/ Daniel J. Duckhorn
   ---------------------------                  -----------------------------
   Its: President                                   Daniel J. Duckhorn
       -----------------------

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